toolchain: banner purge + WHY-only comment sweep (rule 8)

selfhost/, cmd/, internal/ join the tree-wide sweep: every section
banner dies (91 selfhost + the cmd C-style dividers -> 0); narration
and stale contracts deleted (pre-#22 bundler notes, retired
single-PT_LOAD and no-archive claims, superseded ABI tables); every
ref/harec/qbe cite, task cite, encoding/ELF contract, and rule-10
twin pointer kept; lost lifetime/rationale lines restored where the
sweep over-cut (elf_globals ownership, kwtab linear-scan). Comment-
only proven: all five wwstage tool binaries byte-identical across
the sweep; test-commit, test-byteid (161+1399, 0 pinned-divergent),
and test-bootstrap (fixed point + 991-995 byte-id) all exit 0.
The read-through banked 66 latent-bug leads (checkpoint).

selfhost/cmd/w6l/dyn.ww

@@ -1,12 +1,8 @@
-// selfhost/cmd/w6l/dyn.ww — port of cmd/w6l/dyn.c.
+// Port of cmd/w6l/dyn.c.
 //
 // Load a shared object (ET_DYN) so the linker knows which symbols it
 // exports and which DT_NEEDED entry to record. We do not pull bytes
 // from the .so; the dynamic loader maps it at runtime.
-//
-// Each call appends one lso to lnk->sos. l_so_provides_v answers
-// "does this .so export the named symbol, and at which version?" —
-// l_resolve uses that to promote unresolved references to dynamic.
 
 package w6l;
 
@@ -72,8 +68,6 @@ def VD_NEXT:       u64 = 16u64;
 def VA_NAME:       u64 = 0u64;
 def VA_NEXT:       u64 = 4u64;
 
-// ---- little-endian byte readers ---------------------------------------
-
 fn du16(p: *u8, off: u64) u16 = {
 	let b0: u16 = p[off]: u16;
 	let b1: u16 = p[off + 1u64]: u16;
@@ -98,8 +92,6 @@ fn di64(p: *u8, off: u64) i64 = {
 	return du64(p, off): i64;
 };
 
-// ---- C-string helpers --------------------------------------------------
-
 fn dcstrlen(p: *u8) u64 = {
 	let n: u64 = 0u64;
 	for (p[n] != 0u8) { n += 1u64; };
@@ -114,7 +106,6 @@ fn dcstrtostr(p: *u8) str = {
 	return strings.dup(view);
 };
 
-// basename: scan for last '/' and return pointer past it.
 fn dbasename(p: *u8) *u8 = {
 	let n: u64 = dcstrlen(p);
 	let i: u64 = n;
@@ -127,8 +118,6 @@ fn dbasename(p: *u8) *u8 = {
 	return p;
 };
 
-// ---- file slurp --------------------------------------------------------
-
 fn slurpso(path: *u8) (*u8, u64) = {
 	let fd: i32 = os.open(pathstr(path), os.flag.RDONLY, 0i32);
 	if (fd < 0) { return nil, 0u64; };
@@ -151,8 +140,6 @@ fn slurpso(path: *u8) (*u8, u64) = {
 	return buf.ptr, n: u64;
 };
 
-// ---- verdef helpers ----------------------------------------------------
-
 // vdnameat — walk verdef records and return the name (as *u8 into
 // the .so's verstr buffer) for the entry whose vd_ndx == ndx. The name
 // is the first Verdaux's vda_name (subsequent auxes are predecessor
@@ -176,8 +163,6 @@ fn vdnameat(buf: *u8, verdefoff: u64, verdefsize: u64,
 	return nil;
 };
 
-// ---- entry points ------------------------------------------------------
-
 export fn loadso(l: *lnk, path: *u8) i32 = {
 	let buf: *u8;
 	let blen: u64;
@@ -207,7 +192,6 @@ export fn loadso(l: *lnk, path: *u8) i32 = {
 	if (shoff == 0u64) { return soerr("stripped .so unsupported"); };
 	if (shnum == 0u32) { return soerr("stripped .so unsupported"); };
 
-	// Locate the four sections we care about.
 	let idxdynsym:  i32 = -1;
 	let idxdynamic: i32 = -1;
 	let idxversym:  i32 = -1;
@@ -292,8 +276,8 @@ export fn loadso(l: *lnk, path: *u8) i32 = {
 		verstr = buf + vstroff;
 	};
 
-	// Build the lso. Exports are appended in dynsym order so
-	// soprovides_v's first-match semantics match the C version.
+	// Exports are appended in dynsym order so soprovides_v's
+	// first-match semantics match the C version.
 	let so: *lso = alloc(lso { path = dcstrtostr(path), soname = dcstrtostr(sonamecs) })!;
 	let tail: *lexport = nil;
 
@@ -371,7 +355,6 @@ fn soerr(msg: str) i32 = {
 	return -1;
 };
 
-// soprovides — 1 if so exports name, 0 otherwise.
 export fn soprovides(so: *lso, name: str) i32 = {
 	if (so == nil) { return 0; };
 	let e: *lexport = so.exports;